<!DOCTYPE html>
<html>
  <head>
    <style>body { color: green; }</style>
    <link rel="stylesheet" href='data:text/css,body > span { color: red }' type="text/css"/>
    <link rel="stylesheet" href='data:text/css,body > span { color: red }' type="text/css"/>
    <script>
      // Force cloning of the second linked sheet
      document.styleSheets[2].cssRules[0];
    </script>
  </head>
  <body>
    <div><span>This text should be green</span></div>
  </body>
</html>
